/* * ARM Generic/Distributed Interrupt Controller * * Copyright (c) 2006-2007 CodeSourcery. * Written by Paul Brook * * This code is licensed under the GPL. */ /* This file contains implementation code for the RealView EB interrupt * controller, MPCore distributed interrupt controller and ARMv7-M * Nested Vectored Interrupt Controller. * It is compiled in two ways: * (1) as a standalone file to produce a sysbus device which is a GIC * that can be used on the realview board and as one of the builtin * private peripherals for the ARM MP CPUs (11MPCore, A9, etc) * (2) by being directly #included into armv7m_nvic.c to produce the * armv7m_nvic device. */ #include "hw/sysbus.h" #include "gic_internal.h" #include "qom/cpu.h" //#define DEBUG_GIC #ifdef DEBUG_GIC #define DPRINTF(fmt, ...) \ do { fprintf(stderr, "arm_gic: " fmt , ## __VA_ARGS__); } while (0) #else #define DPRINTF(fmt, ...) do {} while(0) #endif static const uint8_t gic_id[] = { 0x90, 0x13, 0x04, 0x00, 0x0d, 0xf0, 0x05, 0xb1 }; #define NUM_CPU(s) ((s)->num_cpu) static inline int gic_get_current_cpu(GICState *s) { if (s->num_cpu > 1) { return current_cpu->cpu_index; } return 0; } /* TODO: Many places that call this routine could be optimized. */ /* Update interrupt status after enabled or pending bits have been changed. */ void gic_update(GICState *s) { int best_irq; int best_prio; int irq; int level; int cpu; int cm; for (cpu = 0; cpu < NUM_CPU(s); cpu++) { cm = 1 << cpu; s->current_pending[cpu] = 1023; if (!s->enabled || !s->cpu_enabled[cpu]) { qemu_irq_lower(s->parent_irq[cpu]); return; } best_prio = 0x100; best_irq = 1023; for (irq = 0; irq < s->num_irq; irq++) { if (GIC_TEST_ENABLED(irq, cm) && GIC_TEST_PENDING(irq, cm)) { if (GIC_GET_PRIORITY(irq, cpu) < best_prio) { best_prio = GIC_GET_PRIORITY(irq, cpu); best_irq = irq; } } } level = 0; if (best_prio < s->priority_mask[cpu]) { s->current_pending[cpu] = best_irq; if (best_prio < s->running_priority[cpu]) { DPRINTF("Raised pending IRQ %d (cpu %d)\n", best_irq, cpu); level = 1; } } qemu_set_irq(s->parent_irq[cpu], level); } } void gic_set_pending_private(GICState *s, int cpu, int irq) { int cm = 1 << cpu; if (GIC_TEST_PENDING(irq, cm)) return; DPRINTF("Set %d pending cpu %d\n", irq, cpu); GIC_SET_PENDING(irq, cm); gic_update(s); } /* Process a change in an external IRQ input. */ static void gic_set_irq(void *opaque, int irq, int level) { /* Meaning of the 'irq' parameter: * [0..N-1] : external interrupts * [N..N+31] : PPI (internal) interrupts for CPU 0 * [N+32..N+63] : PPI (internal interrupts for CPU 1 * ... */ GICState *s = (GICState *)opaque; int cm, target; if (irq < (s->num_irq - GIC_INTERNAL)) { /* The first external input line is internal interrupt 32. */ cm = ALL_CPU_MASK; irq += GIC_INTERNAL; target = GIC_TARGET(irq); } else { int cpu; irq -= (s->num_irq - GIC_INTERNAL); cpu = irq / GIC_INTERNAL; irq %= GIC_INTERNAL; cm = 1 << cpu; target = cm; } if (level == GIC_TEST_LEVEL(irq, cm)) { return; } if (level) { GIC_SET_LEVEL(irq, cm); if (GIC_TEST_EDGE_TRIGGER(irq) || GIC_TEST_ENABLED(irq, cm)) { DPRINTF("Set %d pending mask %x\n", irq, target); GIC_SET_PENDING(irq, target); } } else { GIC_CLEAR_LEVEL(irq, cm); } gic_update(s); } static void gic_set_running_irq(GICState *s, int cpu, int irq) { s->running_irq[cpu] = irq; if (irq == 1023) { s->running_priority[cpu] = 0x100; } else { s->running_priority[cpu] = GIC_GET_PRIORITY(irq, cpu); } gic_update(s); } uint32_t gic_acknowledge_irq(GICState *s, int cpu) { int new_irq; int cm = 1 << cpu; new_irq = s->current_pending[cpu]; if (new_irq == 1023 || GIC_GET_PRIORITY(new_irq, cpu) >= s->running_priority[cpu]) { DPRINTF("ACK no pending IRQ\n"); return 1023; } s->last_active[new_irq][cpu] = s->running_irq[cpu]; /* Clear pending flags for both level and edge triggered interrupts. Level triggered IRQs will be reasserted once they become inactive. */ GIC_CLEAR_PENDING(new_irq, GIC_TEST_MODEL(new_irq) ? ALL_CPU_MASK : cm); gic_set_running_irq(s, cpu, new_irq); DPRINTF("ACK %d\n", new_irq); return new_irq; } void gic_set_priority(GICState *s, int cpu, int irq, uint8_t val) { if (irq < GIC_INTERNAL) { s->priority1[irq][cpu] = val; } else { s->priority2[(irq) - GIC_INTERNAL] = val; } } void gic_complete_irq(GICState *s, int cpu, int irq) { int update = 0; int cm = 1 << cpu; DPRINTF("EOI %d\n", irq); if (irq >= s->num_irq) { /* This handles two cases: * 1. If software writes the ID of a spurious interrupt [ie 1023] * to the GICC_EOIR, the GIC ignores that write. * 2. If software writes the number of a non-existent interrupt * this must be a subcase of "value written does not match the last * valid interrupt value read from the Interrupt Acknowledge * register" and so this is UNPREDICTABLE. We choose to ignore it. */ return; } if (s->running_irq[cpu] == 1023) return; /* No active IRQ. */ /* Mark level triggered interrupts as pending if they are still raised. */ if (!GIC_TEST_EDGE_TRIGGER(irq) && GIC_TEST_ENABLED(irq, cm) && GIC_TEST_LEVEL(irq, cm) && (GIC_TARGET(irq) & cm) != 0) { DPRINTF("Set %d pending mask %x\n", irq, cm); GIC_SET_PENDING(irq, cm); update = 1; } if (irq != s->running_irq[cpu]) { /* Complete an IRQ that is not currently running. */ int tmp = s->running_irq[cpu]; while (s->last_active[tmp][cpu] != 1023) { if (s->last_active[tmp][cpu] == irq) { s->last_active[tmp][cpu] = s->last_active[irq][cpu]; break; } tmp = s->last_active[tmp][cpu]; } if (update) { gic_update(s); } } else { /* Complete the current running IRQ. */ gic_set_running_irq(s, cpu, s->last_active[s->running_irq[cpu]][cpu]); } } static uint32_t gic_dist_readb(void *opaque, hwaddr offset) { GICState *s = (GICState *)opaque; uint32_t res; int irq; int i; int cpu; int cm; int mask; cpu = gic_get_current_cpu(s); cm = 1 << cpu; if (offset < 0x100) { if (offset == 0) return s->enabled; if (offset == 4) return ((s->num_irq / 32) - 1) | ((NUM_CPU(s) - 1) << 5); if (offset < 0x08) return 0; if (offset >= 0x80) { /* Interrupt Security , RAZ/WI */ return 0; } goto bad_reg; } else if (offset < 0x200) { /* Interrupt Set/Clear Enable. */ if (offset < 0x180) irq = (offset - 0x100) * 8; else irq = (offset - 0x180) * 8; irq += GIC_BASE_IRQ; if (irq >= s->num_irq) goto bad_reg; res = 0; for (i = 0; i < 8; i++) { if (GIC_TEST_ENABLED(irq + i, cm)) { res |= (1 << i); } } } else if (offset < 0x300) { /* Interrupt Set/Clear Pending. */ if (offset < 0x280) irq = (offset - 0x200) * 8; else irq = (offset - 0x280) * 8; irq += GIC_BASE_IRQ; if (irq >= s->num_irq) goto bad_reg; res = 0; mask = (irq < GIC_INTERNAL) ? cm : ALL_CPU_MASK; for (i = 0; i < 8; i++) { if (GIC_TEST_PENDING(irq + i, mask)) { res |= (1 << i); } } } else if (offset < 0x400) { /* Interrupt Active. */ irq = (offset - 0x300) * 8 + GIC_BASE_IRQ; if (irq >= s->num_irq) goto bad_reg; res = 0; mask = (irq < GIC_INTERNAL) ? cm : ALL_CPU_MASK; for (i = 0; i < 8; i++) { if (GIC_TEST_ACTIVE(irq + i, mask)) { res |= (1 << i); } } } else if (offset < 0x800) { /* Interrupt Priority. */ irq = (offset - 0x400) + GIC_BASE_IRQ; if (irq >= s->num_irq) goto bad_reg; res = GIC_GET_PRIORITY(irq, cpu); } else if (offset < 0xc00) { /* Interrupt CPU Target. */ if (s->num_cpu == 1 && s->revision != REV_11MPCORE) { /* For uniprocessor GICs these RAZ/WI */ res = 0; } else { irq = (offset - 0x800) + GIC_BASE_IRQ; if (irq >= s->num_irq) { goto bad_reg; } if (irq >= 29 && irq <= 31) { res = cm; } else { res = GIC_TARGET(irq); } } } else if (offset < 0xf00) { /* Interrupt Configuration. */ irq = (offset - 0xc00) * 2 + GIC_BASE_IRQ; if (irq >= s->num_irq) goto bad_reg; res = 0; for (i = 0; i < 4; i++) { if (GIC_TEST_MODEL(irq + i)) res |= (1 << (i * 2)); if (GIC_TEST_EDGE_TRIGGER(irq + i)) res |= (2 << (i * 2)); } } else if (offset < 0xfe0) { goto bad_reg; } else /* offset >= 0xfe0 */ { if (offset & 3) { res = 0; } else { res = gic_id[(offset - 0xfe0) >> 2]; } } return res; bad_reg: qemu_log_mask(LOG_GUEST_ERROR, "gic_dist_readb: Bad offset %x\n", (int)offset); return 0; } static uint32_t gic_dist_readw(void *opaque, hwaddr offset) { uint32_t val; val = gic_dist_readb(opaque, offset); val |= gic_dist_readb(opaque, offset + 1) << 8; return val; } static uint32_t gic_dist_readl(void *opaque, hwaddr offset) { uint32_t val; val = gic_dist_readw(opaque, offset); val |= gic_dist_readw(opaque, offset + 2) << 16; return val; } static void gic_dist_writeb(void *opaque, hwaddr offset, uint32_t value) { GICState *s = (GICState *)opaque; int irq; int i; int cpu; cpu = gic_get_current_cpu(s); if (offset < 0x100) { if (offset == 0) { s->enabled = (value & 1); DPRINTF("Distribution %sabled\n", s->enabled ? "En" : "Dis"); } else if (offset < 4) { /* ignored. */ } else if (offset >= 0x80) { /* Interrupt Security Registers, RAZ/WI */ } else { goto bad_reg; } } else if (offset < 0x180) { /* Interrupt Set Enable. */ irq = (offset - 0x100) * 8 + GIC_BASE_IRQ; if (irq >= s->num_irq) goto bad_reg; if (irq < 16) value = 0xff; for (i = 0; i < 8; i++) { if (value & (1 << i)) { int mask = (irq < GIC_INTERNAL) ? (1 << cpu) : GIC_TARGET(irq + i); int cm = (irq < GIC_INTERNAL) ? (1 << cpu) : ALL_CPU_MASK; if (!GIC_TEST_ENABLED(irq + i, cm)) { DPRINTF("Enabled IRQ %d\n", irq + i); } GIC_SET_ENABLED(irq + i, cm); /* If a raised level triggered IRQ enabled then mark is as pending. */ if (GIC_TEST_LEVEL(irq + i, mask) && !GIC_TEST_EDGE_TRIGGER(irq + i)) { DPRINTF("Set %d pending mask %x\n", irq + i, mask); GIC_SET_PENDING(irq + i, mask); } } } } else if (offset < 0x200) { /* Interrupt Clear Enable. */ irq = (offset - 0x180) * 8 + GIC_BASE_IRQ; if (irq >= s->num_irq) goto bad_reg; if (irq < 16) value = 0; for (i = 0; i < 8; i++) { if (value & (1 << i)) { int cm = (irq < GIC_INTERNAL) ? (1 << cpu) : ALL_CPU_MASK; if (GIC_TEST_ENABLED(irq + i, cm)) { DPRINTF("Disabled IRQ %d\n", irq + i); } GIC_CLEAR_ENABLED(irq + i, cm); } } } else if (offset < 0x280) { /* Interrupt Set Pending. */ irq = (offset - 0x200) * 8 + GIC_BASE_IRQ; if (irq >= s->num_irq) goto bad_reg; if (irq < 16) irq = 0; for (i = 0; i < 8; i++) { if (value & (1 << i)) { GIC_SET_PENDING(irq + i, GIC_TARGET(irq + i)); } } } else if (offset < 0x300) { /* Interrupt Clear Pending. */ irq = (offset - 0x280) * 8 + GIC_BASE_IRQ; if (irq >= s->num_irq) goto bad_reg; for (i = 0; i < 8; i++) { /* ??? This currently clears the pending bit for all CPUs, even for per-CPU interrupts. It's unclear whether this is the corect behavior. */ if (value & (1 << i)) { GIC_CLEAR_PENDING(irq + i, ALL_CPU_MASK); } } } else if (offset < 0x400) { /* Interrupt Active. */ goto bad_reg; } else if (offset < 0x800) { /* Interrupt Priority. */ irq = (offset - 0x400) + GIC_BASE_IRQ; if (irq >= s->num_irq) goto bad_reg; gic_set_priority(s, cpu, irq, value); } else if (offset < 0xc00) { /* Interrupt CPU Target. RAZ/WI on uniprocessor GICs, with the * annoying exception of the 11MPCore's GIC. */ if (s->num_cpu != 1 || s->revision == REV_11MPCORE) { irq = (offset - 0x800) + GIC_BASE_IRQ; if (irq >= s->num_irq) { goto bad_reg; } if (irq < 29) { value = 0; } else if (irq < GIC_INTERNAL) { value = ALL_CPU_MASK; } s->irq_target[irq] = value & ALL_CPU_MASK; } } else if (offset < 0xf00) { /* Interrupt Configuration. */ irq = (offset - 0xc00) * 4 + GIC_BASE_IRQ; if (irq >= s->num_irq) goto bad_reg; if (irq < GIC_INTERNAL) value |= 0xaa; for (i = 0; i < 4; i++) { if (value & (1 << (i * 2))) { GIC_SET_MODEL(irq + i); } else { GIC_CLEAR_MODEL(irq + i); } if (value & (2 << (i * 2))) { GIC_SET_EDGE_TRIGGER(irq + i); } else { GIC_CLEAR_EDGE_TRIGGER(irq + i); } } } else { /* 0xf00 is only handled for 32-bit writes. */ goto bad_reg; } gic_update(s); return; bad_reg: qemu_log_mask(LOG_GUEST_ERROR, "gic_dist_writeb: Bad offset %x\n", (int)offset); } static void gic_dist_writew(void *opaque, hwaddr offset, uint32_t value) { gic_dist_writeb(opaque, offset, value & 0xff); gic_dist_writeb(opaque, offset + 1, value >> 8); } static void gic_dist_writel(void *opaque, hwaddr offset, uint32_t value) { GICState *s = (GICState *)opaque; if (offset == 0xf00) { int cpu; int irq; int mask; cpu = gic_get_current_cpu(s); irq = value & 0x3ff; switch ((value >> 24) & 3) { case 0: mask = (value >> 16) & ALL_CPU_MASK; break; case 1: mask = ALL_CPU_MASK ^ (1 << cpu); break; case 2: mask = 1 << cpu; break; default: DPRINTF("Bad Soft Int target filter\n"); mask = ALL_CPU_MASK; break; } GIC_SET_PENDING(irq, mask); gic_update(s); return; } gic_dist_writew(opaque, offset, value & 0xffff); gic_dist_writew(opaque, offset + 2, value >> 16); } static const MemoryRegionOps gic_dist_ops = { .old_mmio = { .read = { gic_dist_readb, gic_dist_readw, gic_dist_readl, }, .write = { gic_dist_writeb, gic_dist_writew, gic_dist_writel, }, }, .endianness = DEVICE_NATIVE_ENDIAN, }; static uint32_t gic_cpu_read(GICState *s, int cpu, int offset) { switch (offset) { case 0x00: /* Control */ return s->cpu_enabled[cpu]; case 0x04: /* Priority mask */ return s->priority_mask[cpu]; case 0x08: /* Binary Point */ /* ??? Not implemented. */ return 0; case 0x0c: /* Acknowledge */ return gic_acknowledge_irq(s, cpu); case 0x14: /* Running Priority */ return s->running_priority[cpu]; case 0x18: /* Highest Pending Interrupt */ return s->current_pending[cpu]; default: qemu_log_mask(LOG_GUEST_ERROR, "gic_cpu_read: Bad offset %x\n", (int)offset); return 0; } } static void gic_cpu_write(GICState *s, int cpu, int offset, uint32_t value) { switch (offset) { case 0x00: /* Control */ s->cpu_enabled[cpu] = (value & 1); DPRINTF("CPU %d %sabled\n", cpu, s->cpu_enabled[cpu] ? "En" : "Dis"); break; case 0x04: /* Priority mask */ s->priority_mask[cpu] = (value & 0xff); break; case 0x08: /* Binary Point */ /* ??? Not implemented. */ break; case 0x10: /* End Of Interrupt */ return gic_complete_irq(s, cpu, value & 0x3ff); default: qemu_log_mask(LOG_GUEST_ERROR, "gic_cpu_write: Bad offset %x\n", (int)offset); return; } gic_update(s); } /* Wrappers to read/write the GIC CPU interface for the current CPU */ static uint64_t gic_thiscpu_read(void *opaque, hwaddr addr, unsigned size) { GICState *s = (GICState *)opaque; return gic_cpu_read(s, gic_get_current_cpu(s), addr); } static void gic_thiscpu_write(void *opaque, hwaddr addr, uint64_t value, unsigned size) { GICState *s = (GICState *)opaque; gic_cpu_write(s, gic_get_current_cpu(s), addr, value); } /* Wrappers to read/write the GIC CPU interface for a specific CPU. * These just decode the opaque pointer into GICState* + cpu id. */ static uint64_t gic_do_cpu_read(void *opaque, hwaddr addr, unsigned size) { GICState **backref = (GICState **)opaque; GICState *s = *backref; int id = (backref - s->backref); return gic_cpu_read(s, id, addr); } static void gic_do_cpu_write(void *opaque, hwaddr addr, uint64_t value, unsigned size) { GICState **backref = (GICState **)opaque; GICState *s = *backref; int id = (backref - s->backref); gic_cpu_write(s, id, addr, value); } static const MemoryRegionOps gic_thiscpu_ops = { .read = gic_thiscpu_read, .write = gic_thiscpu_write, .endianness = DEVICE_NATIVE_ENDIAN, }; static const MemoryRegionOps gic_cpu_ops = { .read = gic_do_cpu_read, .write = gic_do_cpu_write, .endianness = DEVICE_NATIVE_ENDIAN, }; void gic_init_irqs_and_distributor(GICState *s, int num_irq) { SysBusDevice *sbd = SYS_BUS_DEVICE(s); int i; i = s->num_irq - GIC_INTERNAL; /* For the GIC, also expose incoming GPIO lines for PPIs for each CPU. * GPIO array layout is thus: * [0..N-1] SPIs * [N..N+31] PPIs for CPU 0 * [N+32..N+63] PPIs for CPU 1 * ... */ if (s->revision != REV_NVIC) { i += (GIC_INTERNAL * s->num_cpu); } qdev_init_gpio_in(DEVICE(s), gic_set_irq, i); for (i = 0; i < NUM_CPU(s); i++) { sysbus_init_irq(sbd, &s->parent_irq[i]); } memory_region_init_io(&s->iomem, OBJECT(s), &gic_dist_ops, s, "gic_dist", 0x1000); } static void arm_gic_realize(DeviceState *dev, Error **errp) { /* Device instance realize function for the GIC sysbus device */ int i; GICState *s = ARM_GIC(dev); SysBusDevice *sbd = SYS_BUS_DEVICE(dev); ARMGICClass *agc = ARM_GIC_GET_CLASS(s); agc->parent_realize(dev, errp); if (error_is_set(errp)) { return; } gic_init_irqs_and_distributor(s, s->num_irq); /* Memory regions for the CPU interfaces (NVIC doesn't have these): * a region for "CPU interface for this core", then a region for * "CPU interface for core 0", "for core 1", ... * NB that the memory region size of 0x100 applies for the 11MPCore * and also cores following the GIC v1 spec (ie A9). * GIC v2 defines a larger memory region (0x1000) so this will need * to be extended when we implement A15. */ memory_region_init_io(&s->cpuiomem[0], OBJECT(s), &gic_thiscpu_ops, s, "gic_cpu", 0x100); for (i = 0; i < NUM_CPU(s); i++) { s->backref[i] = s; memory_region_init_io(&s->cpuiomem[i+1], OBJECT(s), &gic_cpu_ops, &s->backref[i], "gic_cpu", 0x100); } /* Distributor */ sysbus_init_mmio(sbd, &s->iomem); /* cpu interfaces (one for "current cpu" plus one per cpu) */ for (i = 0; i <= NUM_CPU(s); i++) { sysbus_init_mmio(sbd, &s->cpuiomem[i]); } } static void arm_gic_class_init(ObjectClass *klass, void *data) { DeviceClass *dc = DEVICE_CLASS(klass); ARMGICClass *agc = ARM_GIC_CLASS(klass); agc->parent_realize = dc->realize; dc->realize = arm_gic_realize; } static const TypeInfo arm_gic_info = { .name = TYPE_ARM_GIC, .parent = TYPE_ARM_GIC_COMMON, .instance_size = sizeof(GICState), .class_init = arm_gic_class_init, .class_size = sizeof(ARMGICClass), }; static void arm_gic_register_types(void) { type_register_static(&arm_gic_info); } type_init(arm_gic_register_types)